The Chinese government has “signed a death warrant for imperilled rhinos and tigers in the wild,” environmentalists warned.

In a move that's enraged and baffled conservationists, the Chinese government announced Monday that it was legalizing the use of rhinoceros horns and tiger bones for traditional medicine and medical research. Trade of the two substances has been banned in China for 25 years.

China's cabinet clarified that only certified hospitals and doctors would be allowed to use the animal parts ― and said the substances would have to come from rhinos and tigers raised on farms, excluding zoo animals.

Environmentalists, however, have denounced the decision as a huge blow to rhino and tiger conservation efforts and a major win for traffickers of illegal animal parts. Leigh Henry of the World Wildlife Fund said it will be "incredibly difficult" to tell rhino and tiger parts obtained legally from farms apart from those acquired from wild animals.

"It's a devastating decision," Henry, the WWF's director of wildlife policy, told The New York Times. "I can't overstate the potential impact."

With only around 3,900 left in the wild, every tiger counts. But China's latest move to lift the ban on tiger bone trade threatens to put a dark cloud over the world's wild 🐯

In traditional Chinese medicine, rhino horns and tiger bones are considered potent healing ingredients that can treat a host of ailments including cancer. There is no scientific research, however, to support these claims. And in recent years, leaders in the field have discouraged the use of both substances, the Times noted.

China has not explained why it decided to reverse its 1993 ban on the animal parts. Peter Knights, chief executive of environmental nonprofit WildAid, said the decision came "completely out of the blue and with no rationale."

The Environmental Investigation Agency, a British nonprofit, called the ban's rollback a "brazen and regressive move which drastically undermines international efforts for tiger and rhino conservation."

"At a single stroke, China has shattered its reputation as a growing leader in conservation following its domestic ban on the sale of ivory at the start of the year," the EIA said, according to the AP.